1. Technical Field
The present invention relates to a motor apparatus including a reluctance motor and a controller controlling the driving of the reluctance motor.
2. Related Art
FIG. 12A shows a known full-pitch winding type three-phase reluctance motor (refer to Japanese Patent No. 3157162). A full-pitch winding type three-phase reluctance motor 100 generates torque by using mutual inductance when current is applied to two of the three phase coils.
However, in a case of the full-pitch winding type, since magnetic fluxes generated by applying current interlink with the windings of all phases, inductive voltage is generated in the winding of each phase, which complicates the control.
Especially in the high-speed rotation region, since the inductive voltage becomes larger, current control becomes complicate due to the influence of the mutual inductance. Hence, generating appropriate torque becomes difficult.
For example, according to the control disclosed in Japanese Patent No. 3157162, as shown in FIG. 12B, when changing from a state where current is applied to an A phase coil and a C phase coil to a state where current is applied to the A phase coil and a B phase coil, decreasing the current applied to the C phase coil and increasing the current applied to the B phase coil are simultaneously started.
In this case, after the change, magnetic fluxes generated by the current of the windings of the A phase and the B phase act in a predetermined direction so as to prevent the current of the C phase coil from decreasing. Hence, current components which do not contribute to the torque remain in the C phase coil, thereby decreasing the torque. As a result, desired torque cannot be obtained.